Microelectronic National Centre of Barcelona, 08193 Bellaterra, Barcelona, Spain; Department of Analytical Chemistry, Faculty of Chemistry, University of Sevilla, c/Prof. García González s/n, 41012 Seville, Spain; Department of Analytical Chemistry, Universitat Autónoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
Department of Analytical Chemistry, Universitat Autónoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
Talanta. 2017 Apr 1;165:496-501. doi: 10.1016/j.talanta.2016.12.059. Epub 2016 Dec 23.
A fast double-flow microfluidic based liquid phase microextraction (DF-µLPME) combined with a HPLC-UV procedure using diode array detection has been developed for the determination of the four most widely used parabens: Ethyl 4-hydroxybenzoate (EtP), Propyl 4-hydroxybenzoate (PrP), Butyl 4-hydroxybenzoate (BuP) and IsoButyl 4-hydroxybenzoate (iBuP) in water samples. Parabens have successfully been determined in environmental (lake and river water) samples with excellent clean up, high extraction efficiency and good enrichment factor using double-flow conditions. The microfluidic device consists of two micro-channels, which contain the acceptor and sample solution separated by a flat membrane (support liquid membrane). The sample (0.32mM HCl) and acceptor phase (5.6mM NaOH) are delivered to the µLPME at 10µLmin and 1µLmin flow rate, respectively. The extraction efficiencies are over 84% for all compounds in water samples with enrichment factors within the range of 9-11 and recoveries over 80%. The procedure provides very low detection limits between 1.6 and 3.5µgL. The extraction time and the volume required for the extraction are 5min and 50µL, respectively; which are greatly lower compared to any previous extraction procedure for parabens analysis. In addition, this miniaturized DF- µLPME procedure significantly reduces costs compared to not only the existing methods for paraben detection, but also to the existing analytical techniques for sample preparation.
一种快速双流微流控液相微萃取（DF-µLPME）与高效液相色谱-紫外检测联用，已被开发用于测定四种最广泛使用的对羟基苯甲酸酯：乙基 4-羟基苯甲酸酯（EtP）、丙基 4-羟基苯甲酸酯（PrP）、丁基 4-羟基苯甲酸酯（BuP）和异丁基 4-羟基苯甲酸酯（iBuP）在水样中。在环境（湖泊和河水）水样中，通过双流条件，使用双流向条件成功地对这些对羟基苯甲酸酯进行了测定，具有出色的净化效果、高萃取效率和良好的富集因子。微流控装置由两个微通道组成，其中含有接受器和样品溶液，由一个平板膜（支撑液膜）隔开。样品（0.32mM HCl）和接受相（5.6mM NaOH）分别以 10µLmin 和 1µLmin 的流速输送到 µLPME。在水样中，所有化合物的萃取效率均超过 84%，富集因子在 9-11 范围内，回收率超过 80%。该方法提供了非常低的检测限，范围在 1.6 到 3.5µgL 之间。萃取时间和萃取所需的体积分别为 5min 和 50µL，与任何以前的对羟基苯甲酸酯分析萃取程序相比，大大降低。此外，与现有的对羟基苯甲酸酯检测方法相比，这种微型化的 DF-µLPME 程序不仅显著降低了成本，而且与现有的样品制备分析技术相比，也降低了成本。
